An abscess is a pocket of pus from an infection. An anorectal abscess occurs in the area of the anus or rectum. The anus is the last part of your digestive tract. It's at the end of your rectum. It has a ring of muscle (sphincter) that opens during a bowel movement to allow stool (feces) to pass through. There are many glands within the anus. If one of these glands gets clogged, it can get infected. An abscess may then form.

An abscess in this area is usually caused by a clogged anal gland. It may be clogged with bacteria or stool.

Anorectal abscess occurs more often in people who are biologically male than in people who are biologically female. It usually happens between ages 20 and 60, with the average age being 40.

A person is more at risk for anorectal abscess if they:

• Have inflammatory bowel disease (IBD), such as Crohn's disease.
• Take certain medicines, such as chemotherapy for cancer.
• Have objects placed in the rectum, such as during sex.
• Take medicines that suppress the immune system after an organ transplant.
• Are pregnant.
• Have diabetes.
• Have an anal fissure, for example from constipation, that doesn't heal.
• Have a sexually transmitted infection (STI).

Symptoms can occur differently in each person. They can include:

• Severe pain or discomfort near the anus. The pain is constant. But it may not happen with a bowel movement.
• Tiredness.
• Fever.
• Night sweats.
• Constipation.
• Painful bowel movements.
• Swelling or redness near the anus.
• A lump or painful, hardened tissue near the anus.
• Pain in the lower belly (abdomen).
• Fluid or pus leaking from the anus or buttocks.

The symptoms of an anorectal abscess may look like other health conditions. See your doctor for a diagnosis.

Your doctor will ask about your symptoms and health history. They will do a physical exam. The physical exam will include your anal area. You may also have:

• Digital rectal exam. The doctor may gently put a gloved, lubricated finger into your anus. A tool called a speculum may also be used. It is inserted into the anus and gently expanded. This lets your doctor see more of the anal area.
• Proctosigmoidoscopy (sigmoidoscopy). A flexible tube with a light and a tiny camera is placed in the anus. This lets your doctor look at the area.
• Imaging test. You may also have an MRI, CT scan, or ultrasound (sonogram). One of these tests may be done to find the exact location of the abscess.

Treatment will depend on your symptoms, your age, and your general health. It will also depend on how severe the condition is. In some cases, a full anorectal exam under anesthesia is needed. This is to help the doctor decide on the best treatment. Treatment may include:

• Draining the abscess. The doctor will make an incision in the skin near the anus so the pus can drain. This eases the pressure and lets the tissues heal. This can be done in a doctor's office. If you have a large or deep abscess, you may need to be in the hospital and possibly have surgery under general anesthesia. You may also need to be in the hospital if your immune system is weak and you get infections easily.
• Local anesthesia. This can help ease pain.
• Antibiotic medicine. In some cases, the doctor may prescribe antibiotics. This medicine treats infection. But antibiotics alone are often not helpful. This is why draining the abscess is very important.

Talk with your doctor about the risks, benefits, and possible side effects of all treatments.

Many people with an anorectal abscess develop an anal fistula. This is a small tunnel that opens up between the inside of the anus and the skin next to the anus. Pus from the abscess seeps out of this tunnel. A fistula often needs to be fixed with surgery.

Other possible complications include:

• Pain.
• Infection.
• The abscess coming back.

You can reduce your chances of having this condition by managing diabetes, STIs, and other risk factors. If you have IBD, you may need medicine to help prevent anorectal problems such as an abscess.

Contact your doctor if you have pain, discomfort, or swelling in the anus or rectum.

• An abscess is a pocket of pus from an infection. There are many glands within the anus. If one of these glands gets clogged, it can get infected. An abscess may then form.
• Symptoms can include pain and fever.
• You are more at risk for an anorectal abscess if you are pregnant, or if you have diabetes or IBD.
• You may have a digital rectal exam and a proctosigmoidoscopy.
• The abscess may be drained in a doctor's office or in the hospital.
• Many people with an anorectal abscess develop an anal fistula. This is a small tunnel that opens up between the inside of the anus and the skin next to the anus. A fistula often needs to be repaired with surgery.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions.